You get eight solid pages of information on tieflings in general, in addition to their noble ancestry and history (including sample noble houses and noble backgrounds). It then moves on to discussing tieflings by power source--including the psychic source--with a paragon path for each, and all of this eats up 24 pages of a 32-page book. Like PHR: Dragonborn, I could easily see using all of these. Where before I was torn on a paragon path for my warlord, I'm absolutely sold on the Turathi hell-kite (head-butt attack? FUCK YES). Shit, the redeemer of the damned (primal paragon path) has you channeling the damned spirits of your ancestors.

And then, there's feats. Its a hefty section with 31 feats, and I particularly love the tail feats. Clever Tail lets you use your tail to stow/retrieve objects, including making unpenalized Thievery checks, while Tail Slide lets you slide an ally when you shift. There are more warlock feats that help make tieflings the best warlocks possible, such as Blood Pact of Cania (damage bonus when you use warlock attacks that rely on Constitution) and Hellish Blast (eldritch blast becomes a fire attack and gains a damage bonus), but many classes get something and most of them are for tieflings in general.

The book then wraps up with some new magic item properties, fluff information on tiefling quests (two more pages), and the heir of the empire epic destiny. Heir of the empire gives you a Int and Cha bonus, bonus on Cha skills, causes infernal wrath to auto-prone targets, and lets you dominate the first creature you hit in an encounter (for free). Ruler of life and death lets you auto-dominate a slain creature, causing them to get back up and fight for you, and when they finally save against the effect they die.